Air circulating device for hot air furnaces



June 23, 1931.

, E. AGKERMAN AIR cmcuwrm DEVICHFOR HOT A IR rumucss 2 Sheets-Sheet 1 Filed Jan. 8. 1929 AIR OIRCULATINGDEVIGE FOR How AIR FURNACES A Filed Jan. 8. 1929 2 Sheets-Sheet 2 Aww Patented June 23, 1931 UNITED STATES EMIL ACKERMAN, or CHICAGO, ILLINOIS AIR CIRCULATING DEVICE FOR HOT AIR FURNACES Application filed January 8, 1929. Serial No. 331,087.

Numerous means and various devices have 1 been developed for creating such a draft in hot air furnaces but, until the development of the present invention, no suitable means, applicable to known types of hot air furnaces, has been perfected. Of the various devices 2 previously developed, each is provided with means for checking the counteracting effect of a back pressure created within the air intake duct, by the forced draft passing there through. This means provided for the clos-' ing of auxiliary air passages in the air circulating device, the closing means commonly employing movable louvres actuated either by the direct draft or by the back pressure.

It can readily be appreciated that the em ployment of movable louvres in an air intake duct, especially when the actuation of said louvres is dependent upon forced draft or back pressure, does not provide a device which may be relied upon as being positive in operation. Any obstruction, such as,for example, small particles of dirt, lodging in the path of the air operated louvres which louvres must necessarily be very freely mounted, will tend to prevent their actuating,

thus defeating the purpose thereof. Should the auxiliary air passages be left open, when the force draft creating means is in opera tion, the back pressure created in the air duct will cause such a circulation of air therein that no benefit will be. derived from the device.

.The foregoing recites'but a few of the objectionable features which have been developed as the art of artificially creatlng a forced draft in hot air furnaces progressed,

and it is, therefore, one of the principal objects of the present invention to provide an air circulating device for hot air furnaces having means rigidly'mounted therein for directing the flow of air through the entire 7 device.

It is another object of this invention to provide a novel device for creatinga forced draft in the. air passages of a hot air furnace which will be noiseless and positive in 0 operation, the means for creating the draft therein being resiliently mounted, thus eliminating undesirable noise normally set up by the vibration of such means;

Another object of the present invention resides in the provisionof a device for creating aforced draft in the air passages of hot air furnace having but few moving parts and is therefore, inexpensive to manufacture and maintain.

These and such other objects as will appear hereinafter as the description proceeds will be more readily understood from the following specification, reference being had to the accompanying drawings, in which:

Fig. 1 is a perspective view of the im* proved air circulating device mounted in the intake duct of a furnace.

Fig. 2 is an elevational view of the device, as viewed from the air inlet side.

Fig. 3 is a horizontal central sectional view through the novel air circulating device, taken on line 3-3 of Fig. 2, having portions of the air intake duct attached thereto.

Fig. 4; is a fragmental elevational view 85 similar to Fig. 2, of another form of the invention, showing a modified arrangement of louvres therein.

Fig. 5 is a fragmentary horizontal sec-. tional view similar to Fig. 3, but showing a further modification of the invention.

The air circulating device shown in the drawings preferably comprises a frame member, having means for creating av forced draft 95 mounted thereon, which provides a unitary structure for mounting within an air intake duct ofa hot air furnace. This frame mem-.

ber comprises a substantially rectangular frame 11 formed of sheet metal and having 109 outwardly directed flanges 12 on each edge thereof to provide means for securing thereto the flanged ends of the air intake duct 13, of the furnace 14. Resiliently mounted on the rectangular frame member 11, and extending rearwardly therefrom, is a blower fan motor 15, said blower fan motor being suitably mounted on a panel 16. The panel 16 is ri idly secured in any suitable manner in the said rectangular frame member 11 midway the end walls thereof.

A centrally located opening 1'? is provided in the panel 16 to permit passage of a forced draft therethrough, and mounted around the circumference of said opening, at spaced intervals, are a plurality of mounting arms 18, which mounting arms form means for securing the motor 15 to said panel.

The blower fan motor 15 is preferably secured to the mounting arms 18 in such a. manner that most all of the vibration set up by said motor is absorbed thereby, thus eliminating the noises created within the device by such vibration. The mounting 3 means preferably employed for absorbing the ibration of the motor, comprises a plurality of spaced ears 19 on the housing of the motor 15. Each of these ears is provided with a threaded bore adapted to receive a bolt 21, which bolt passes through an apertured boss 22, provided therefor on the intu-rned end of each arm 18, and is threaded into the apertured ear 19. Rubber or other similar resilient material is preferably employed to provide washers 23, which are placed over the bolts 21, on either side of each of the apertured bosses 22, and a metallicretaining washer 2 5i is placed on each of said bolts beneath the head thereof. This construction provides avery secure mounting for the motor 18, as well as insulating it therefrom to the extent that the vibration set up by said motor is absorbed by the insulation, thereby making the device extremely quite in operation.

The motor shaft 256; extends inwardly a short distance toward the panel 16 andhas rigidly mounted thereon a blower fan 25 which blower fan is preferably of a size sufficiently large to cover the entire area of the opening 17, in the panel.

As shown in the drawings, the panel 16 is mounted near the inlet side of the rectangular frame member 11 and as previously mentioned, is centrally located relative to the vertical end walls of said frame to provide an air passage on either side thereof. Flanges 26 are formed on each vertical edge of said panel to add strength thereto, which flanges are. bent inwardly for a purpose to be described later. Centrally located in the rectangular frame member, adjacent the panel 16, is a baffle plate 27, said baffle plate being formed substantially V shaped, in cross section' and having its apex directed towards and in vertical alignment with the blower fan motor 15.

It will be readily understood, from Fig. 3, that, when the blower fan 25 is in operation, the draft created thereby is forced through the opening 17, in the panel 16, and, the baffle 27 will deflect the said forced draft toward each vertical side wall of the air intake duct 13.

This means of deflecting the forced draft will serve to prevent air being forced direct- 1y forward of the blower fan, thereby eliminating back pressure along the side walls of the intake duct, which back pressure causes air to flow rearwardly through and beyond the air circulating device. The circulation of air set up by a back pressure of this nature creates a continuous cycle of air in the vicinity of said device, thereby defeating the pur pose of the forced draft.

Of course, additional means must be provided in the air passages to further aid the counteraction of the air currents created by the blower fan, as mere divergence of the forced air draft towards the side walls of the air duct, by the baffle plate 27 will not serve to completely eliminate back pressure therein. This additional means is. provided for by the installation of a plurality of baffle plates, or louvres, 28 in said air passages, which bafrle plates are also preferably V- shaped in cross section, and are secured, in a vertical position, to the top and bottom walls of the rectangular frame member 11 by the flanges 29, rigidly secured to said walls by welding or, any other similar means may be employed.

The baffle plates, or 'louvres, 28 preferably have their apex disposed toward the center of the air circulating device so that air siphoned through the air passages by the forced draft, will assume the same general direction of the deflected forced draft, thereby becoming a part thereof, as indicated by the arrows in Fig. 3, rather than tending to counteract the direction of said forced draft.

To. provide a proper semi-closure for the air passages, adjacent the end walls of the frame 11, it is preferable to provide a vertically disposed louvre 30, which is adapted to be rigidly secured to the housing 11 and extend inwardly a short distance from theend walls thereof, as shown.

Of course, in such, air circulating devices as those described in the, foregoing, complete elimination of back pressure in the air duct is practically impossible.

However, with thepresent device any'back pressure created in; the air duct thoughvery, small will be in the substantial. center thereof, that is: directly behind the baffle 27,.

rather than along the side walls of the duct,

direction intothepath of the forced. draft.

,. of the forced draft.

When the blower fan 25 is not in operation air may freely pass through the central opening 17 and through the air passages adjacent the panel 16. Thus at no time will a hot air heating system, employing the improved air circulating device, be deprived of a plentiful supply of fresh inflowing air, the baffle plates 28, being of such construction as to offer little or no resistance to the air siphoned therethrough by the forced draft.

In the form of the invention shown in Fig. 4, the centrally located Vertically disposed V-shaped bafile plate employed in the preferred form of the invention is disposed of,

and, mounted in place thereof is a substantially conical baffle member 31. This baffle member 31 is centrally supported, relative to the opening 17, in the panel 16, by a pair of oppositely disposed straps 32, which straps are preferably riveted to the outside periphery of said baffle member and have their outer ends bent substantially at right angles, as shown, and secured to the top and bottom walls of the rectangular frame 11.

With a bafile of this type employed, air forced through the aperture 17 by the blower fan 25, will be directed towards all four Walls of the air duct 13. Any back pressure created within the duct will cause air currents to flow rearwa'rdly at the substantial central portion thereof, that is; directly behind the conical member, whereupon when reaching a point directly to the rear thereof said air currents will be drawn into the path However, it is to be understood that this back pressure is very minute, in the foregoing devices, as consider able resistance is offered by the blower fan, which resistance increases as the fan continues in operation over a period of time.

In this form of the invention the air pas sages adjacent the panel 16 are preferably provided with a plurality of horizontally disposed louvres 33 which are rigidly secured in the frame 11 and are directed inwardly and upwardly. While these louvres act different than those illustrated in the preferred form of the invention, they serve with similar results for preventing any back flow of air therethrough. The air, siphoned through air passages having horizontally disposed upwardly directed louvres mounted therein, will be directed upwardly into the path of the forced draft.

The form of the invention disclosed in Fig. 5 is somewhat similar to that shown in Figures 1 to 3, inclusive. However, in this form, the vertically disposed V-shaped baffle plate 27 and louvres 28 are not employed and the conical baffle member 31 is mounted in place of the former. Louvres 34, comprising flat metallic strips, are angularly mounted in a vertical plane, relative to the side walls of the frame 11, in the air passages for directing air passing therethrough towards said side to be understood that this device is capable of embodying variations and modifications in' detailed structure without departing from the spiritof the invention nor the scope of the appended claims.

I claim:

1'. An. air circulating device for a furnace,

having in combination, a blower fan, a fixed deflector adjacent said blower fan, an air passage on each side of said blower fan'for spreading the draft created by said blower fan, and a pluralityof fixeddeflectors in said air passages. V g

2. Aniair circulating device for a furnace, comprising in combination, a frame having a panel mounted therein, a blower fan mounted over an opening in said panel, a deflector adjacent said opening, an air pas sage on each side of said panel and a plurality of deflectors in said air passages for directing air outwardly of said panel.

3. An air circulating device for a furnace, having in combination, a frame adapted to be mounted in the air intake duct, a panel in said frame, a blower fan mounted on said panel adjacent an opening therein for creating a forced draft therethrough, means in the path of said forced draft for directing the flow thereof towards the walls of said duct, air passages in said frame, and a plurality of vanes in said air passages for deflecting air passing therethrough outwardly.

4. In a furnace, an air circulating device comprising, in combination, a frame, a blower fan mounted in said frame for creating a draft therethrough, a vane in said frame for directing the draft passing therethrough outwardly, air passages in said frame, and a plurality of vanes for directing the flow of air through said air passages.

5. A furnace having an air circulating device mounted therein having in combination, a rectangular frame adapted to be mounted in the air intake duct of said furnace, a blower fan mounted in said frame for c'reating a forced draft therethrough, means in said frame for directing said draft towards each side of said duct, and a plurality of air 1 passages in said frame having fixed louvres mounted therein for directing air passing therethrough in the same direction as said forced draft.

6. In a furnace, an air circulating device comprising a rectangular frame adapted to be mounted in the air intake duct thereof, a blower fan resiliently mounted on said frame for creating a forced draft therethrough, a vertically disposed baffle mountedv in: said frame for directing said forced draft towards each vertical side Wall of. said air duct, and a plurality of air passages in said frame having fixed vertical vanes mounted therein for deflecting air passing therethrough into the path of the forced draft.

7. In combination With a blower fan adapted to be mounted Within the air duct of a furnace for creating a forced draft there- L through, means associated with said fan for deflecting the passage of air in said duct; said means comprising a fixed vertically disposed angular baffie plate mounted in the path of said forced draft, and a plurality of fixed angular baffle plates mounted in said duct for directing air into the path of the forced draft.

In testimony whereof I affix my signature at 10' South La Salle Street, Chicago, lllie nois.

EMIL ACKERMAN. 

